.mulselet-chk{
    display: inline-block;
    width:22px; height:22px;
    vertical-align: middle;
    text-align: center;
    background: url("../images/index.gif") -66px 0;
    overflow: hidden;
}
.mulselet-checked{
    background: url("../images/index.gif") -66px -22px;
}